Helical turbine assembly operable under multidirectional gas and water flow for power and propulsion systems

ABSTRACT

A helical turbine assembly capable of providing high speed unidirectional rotation under a multidirectional ultra low-head fluid flow is disclosed. The assembly comprises an array of helical turbine units or modules arranged, vertically or horizontally, to harness, for example, water or wind power. Each turbine unit or module comprises a plurality of helical blades having an airfoil profile. The modules for wind power may be mounted to rotatable shafts supported by lightweight structures anchored by guy wires to the ground. The helical turbine can also a provide ship propulsion by utilizing the power of ocean waves. In a further embodiment, a cylindrical distributor is provided in the helical turbine to channel the fluid flow to the blades of the turbine, thereby increasing efficiency and power output. The helical turbine with distributor may be used to lift or lower a body either being submerged into a fast stream or dragged in the fluid. The turbine may also include two or more rings of helical blades to increase torque and power output.

This application is a a continuation of application Ser. No. 08/452,824,filed May 30, 1995, entitled: HELICAL TURBINE ASSEMBLY OPERABLE UNDERMULTIDIRECTIONAL FLUID FLOW FOR POWER AND PROPULSION SYSTEMS, now U.S.Pat. No. 5,642,984 which is a continuation-in-part of application Ser.No. 08/241,762, filed Apr. 22, 1994, now U.S. Pat. No. 5,451,137; whichis a continuation-in-part of application Ser. No. 08/179,965, filed Jan.11, 1994, now U.S. Pat. No. 5,451,138.

FIELD OF THE INVENTION

This invention relates to turbines and more particularly to turbinescapable of unidirectional rotation under multidirectional fluid flowsfor use with hydro-pneumatic, hydro, wind, or wave power systems.

BACKGROUND OF THE INVENTION

A unidirectional turbine is a turbine capable of providingunidirectional rotation from bidirectional or reversible fluid flow,such as in tidal estuaries or from shifting wind directions. Generally,three basic types of unidirectional reaction turbines are known, theWells turbine, the McCormick turbine, and the Darrieus turbine.

The Wells reaction turbine is a propeller-type turbine that comprises aseries of rectangular airfoil-shaped blades arranged concentrically toextend from a rotatable shaft, as shown in FIG. 1. Typically, theturbine is mounted within a channel that directs the fluid flow linearlyalong the axis of the rotatable shaft. The blades are mounted to extendradially from the rotatable shaft and rotate in a plane perpendicular tothe direction of fluid flow. Regardless of the direction in which thefluid flows, the blades rotate in the direction of the leading edge ofthe airfoils, which, in FIG. 1, is counterclockwise.

The Wells turbine is capable of rapid rotation. The outer ends of itsblades move substantially faster than the flowing air, causing highnoise. Also, its efficiency is relatively low, because the effectivesurface area of the airfoil-shaped blades is limited to the outer tips,where the linear velocity is greatest. The blades cannot capture asubstantial amount of the available energy in the fluid flowing closerto the shaft.

The McCormick turbine comprises a series of V-shaped rotor bladesmounted concentrically between two series of stator blades, as shown inFIG. 2. The rotor blades are mounted for rotation in a planeperpendicular to the direction of fluid flow. The stator blades directfluid flow to the rotor blades. To achieve unidirectional rotation withbidirectional fluid flow, the outer stator blades are open to fluidflowing from one direction, while the inner stator blades are open tofluid flowing from the opposite direction.

The McCormick turbine is more quiet and could be more efficient than theWells turbine. However, its rotational speed is too slow for directoperation of an electric generator. Its configuration is also complexand expensive to manufacture.

The Darrieus machine is a reaction turbine with straight airfoil-shapedblades oriented transversely to the fluid flow and parallel to the axisof rotation, as shown in FIG. 3. The blades may be attached to the axisby circumferential end plates, struts, or by other known means. In somevariations, the blades are curved to attach to the ends of the axis. ADarrieus reaction turbine having straight rectangular blades, mountedvertically or horizontally in a rectangular channel, has been placeddirectly in a flowing body of water to harness hydropower. The Darrieusturbine rotates with a strong pulsation due to accelerations of itsblades passing through the higher pressure zones in the fluid thatlowers the efficiency of the turbine.

Thus, a need still exists for a quiet, efficient, uniformly rotational,simple, unidirectional turbine that can operate at high speeds.

SUMMARY OF THE INVENTION

The present invention provides a unidirectional helical turbine capableof achieving high speeds needed for industrial electric generators. Theturbine comprises a working wheel having a plurality of airfoil-shapedhelical blades mounted transversely to the direction of fluid flow forrotation in a plane parallel to the direction of fluid flow. The bladesextend between two supporting members, such as a pair of parallel discs,mounted on a rotatable shaft. The blades rotate in the direction of theleading edge of the airfoil, regardless of the direction of fluid flow.

The helical configuration ensures that a portion of the blades arealways positioned optimally with respect to the fluid flow, therebycreating maximum thrust to spin the turbine. The continuous helicalblades provide a continuous speed of rotation uninterrupted byaccelerations and decelerations that accompany the Darrieus turbine asthe blades pass the least and most efficient thrust zones. The skewedleading edges of the helical configuration further reduce resistance tothe turbine rotation. The helical blades are operable with or without achannel to direct the fluid flow.

In a further embodiment, a cylindrical distributor is provided withinthe helical blades, to channel the fluid to the blades of the turbine,thereby increasing the fluid velocity near the blades and the poweroutput of the helical turbine. The helical turbine combined with thecylindrical distributor attached to the turbine may also be used as anapparatus for lifting or lowering bodies such as submarines orsubmersible barges.

The helical turbine may also be provided with multiple layers or ringsof concentrically arranged helical blades. The blades of adjacent ringsare shifted circumferentially such that they do not overlap each otherin the fluid flow. That is, the inner blades are positioned within thespaces between the outer blades. The multilayer arrangement increasesthe torque and power output.

In a case when the helical turbine is used with a hydro-pneumatic energyconverter, a channel interconnects a pair of chambers in which air isalternately compressed and expanded due to the alternate filling andemptying of the chambers with water. The alternate compression andexpansion causes the air flow to alternate in direction through theconnecting channel. The helical turbine, mounted in the channel, is inthis manner able to capture the energy in the flowing air and convert itto rotary mechanical energy. The turbine is connected to an electricgenerator for generation of electrical energy. No additional gearingspeed increaser is usually required, since the turbine rotates fastenough for conventional generators.

In a hydro application, the helical turbine may be mounted in a vessellocated in a current of about 5 feet per second or greater, such as in atidal channel. The turbine is located below the surface of the water,where the current velocity is greatest, and is retained in that locationby virtue of the vessel's rise and fall with the water. The helicalturbine embodiment is particularly suited to this application. A housingto channel the flow to the turbine may by provided if desired, but isnot necessary if the current velocity is sufficiently great. The turbineis connected to a suitable electric generator, which may be mounted onthe vessel in a water tight chamber. The turbine can also be used inconventional applications, such as in dams.

The helical turbine is also efficiently configured in a modular formcomprising, preferably, two or more helical blades in spirals extendingfrom one end to the other. For wind power applications, a plurality ofmodules is arrayed, vertically or horizontally, on rotatable shaftswhich are supported by lightweight structures anchored to the ground byguy wires. The optimally designed modules provide unidirectional anduniform, non-oscillating rotation in any non-zero angle between theturbine shaft and wind direction.

The helical turbine is also useful to provide propulsion or supplementengine-driven propulsion of a marine vessel utilizing the power of oceanwaves. The helical turbine is operable under the multidirectionaloscillations of ocean waves and can develop a substantial axial torqueuseful in the propulsion of marine vessels.

DESCRIPTION OF THE DRAWINGS

The invention will be more fully understood from the following detaileddescription taken in conjunction with the accompanying drawings inwhich:

FIG. 1 is a schematic illustration of a prior art Wells turbine;

FIG. 2 is a schematic illustration of a prior art McCormick turbine;

FIG. 3 is a schematic illustration of a prior art Darrieus turbine;

FIG. 4 is a cross-sectional side view of a helical turbine according tothe present invention;

FIG. 5 is a frontal view of a helical turbine according to the presentinvention;

FIG. 6 is a cross-sectional view along line VI--VI of FIG. 5;

FIG. 7 is a cross-sectional view along line VII--VII of FIG. 5;

FIG. 8 is a schematic cross-sectional side view of a turbine accordingto the present invention illustrating zones of thrust efficiency;

FIG. 9 is a fragmentary view of a single turbine blade of the embodimentof FIG. 5 illustrating resolution of the thrust force on the blade;

FIG. 10 is a schematic illustration of the turbine of the presentinvention in operation in a hydro-pneumatic power system;

FIG. 11 is a perspective view of a system mounted on a catamaran forharnessing hydro energy according to the present invention;

FIG. 12 is a frontal view of the system of FIG. 11;

FIG. 13 is a side view of the system of FIG. 11;

FIG. 14 is a schematic view of a helical turbine module of a furtherembodiment of the present invention;

FIG. 15 is a schematic view of an array of the turbine modules of FIG.14 arranged vertically;

FIG. 16 is a schematic view of an array of the turbine modules of FIG.14 arranged horizontally;

FIG. 17 is a front view of a further embodiment of a helical turbine ofthe present invention embodying a cylindrical distributor;

FIG. 18 is a cross-sectional side view of the helical turbine of FIG.17;

FIG. 19 is a side view of a marine vessel propulsion system of thepresent invention;

FIG. 20 is a front view of the propulsion system of FIG. 19;

FIG. 21 is a schematic view of an array of turbines connected via atransmission to a single generator;

FIG. 22 is a cross-sectional side view of a multilayer helical turbineof the present invention;

FIG. 23 is a schematic front view of a multilayer helical turbine of thepresent invention;

FIG. 24 is a schematic view of a helical turbine and cylindricaldistributor used to maintain flotation of a submerged object bydeveloping a lifting force;

FIG. 25 is an end view of the helical turbine and submerged object ofFIG. 24; and

FIG. 26 is a schematic view of a helical turbine as a wind sail for amarine vessel.

DETAILED DESCRIPTION OF THE INVENTION

A helical turbine according to the present invention is shown in FIGS.4, 5 and 14. The turbine 10 comprises a plurality of airfoil-shapedhelical turbine blades 12 supported for rotation on a rotatable shaft 14by one or more turbine blade support members 16. The airfoil-shapedblades may be formed from any suitable material, such as a steel orplastic material. The blade support members 16, which, in the embodimentshown, comprise parallel, circular discs, are fixedly mounted in spacedrelation on the rotatable shaft 14 such that rotation of the blades 12and discs 16 causes the shaft 14 to rotate as well. The blades 12 arefixedly mounted to extend helically from one disc 16 to the other disc16 and are spaced radially from the rotatable shaft 14. The bladesupport members may comprise other configurations, such as a singlecentral disc, radial spokes, or the like.

The turbine 10 may be free in a fluid flow or may be mounted inside achannel 20 or duct. The channel, if provided, generally comprisesopposed side walls 22,24, a top wall 26, and a bottom wall 28 which forma passage 30 for directing the flow of fluid to the turbine. The shaft14 is oriented transversely to the flow of fluid through the channel andis mounted for rotation, for example, via bearings in the side walls ofthe channel. Also, with the helical configuration, it is possible toeliminate the channel entirely if desired.

Each helical blade 12 has an airfoil shape with a leading edge 36 and atrailing edge 38 oriented transversely to the flow of fluid. Preferably,the blades are formed with a suitable airfoil profile, as is known inthe art. The blades 12 are mounted at the outermost diameter of thecircular discs 16 and are generally oriented to lie along a circledefined by the outer diameter of the discs such that the chord of eachairfoil generally but not necessarily forms the chord of an arc of thecircle. Any number of blades may be provided.

Referring to FIG. 4, fluid flowing in the direction of arrows 40 alongthe channel 20 causes the turbine 10 to rotate in the direction of theleading edge 36 of the blades as shown by arrow 42. Similarly, fluidflowing in the opposite direction along the channel 20 also causes theturbine to rotate in the same direction, the direction of the leadingedge 36 of the blades 12. As is apparent, the turbine rotates in a planeparallel to the flow of fluid. The blades 12 should be spaced radiallyas far from the rotatable shaft 14 as practicable to capture thegreatest amount of energy in the flowing fluid. The skewed leading edges36 further reduce resistance to the turbine rotation.

The helical blades may be divided into two halves 102a, 102b, as shownin FIG. 5, in which one half is a left-handed helix and the other halfis a right-handed helix. In this manner, the components of the thrustforce which extend parallel to the shaft 14 cancel each other out, asdiscussed further below. However, all left-handed or all right-handedhelixes or any other suitable helical configuration may be provided ifdesired. The blades are fixedly attached at their ends to extendtransversely from one disc to the other disc, creating a non-solid,fluid transmitting cylinder. In addition, any suitable number of radialspokes 110 may be provided which extend perpendicularly from therotatable shaft to each blade at spaced intervals. Such radial spokesincrease the integrity and structural strength of the system.Alternatively, the blade support members may comprise otherconfigurations, such as a single central disc, radial spokes alone, orthe like.

In addition, a portion of the blades 12 are always positioned in themost efficient zones of the fluid pressure, thereby creating maximumthrust to spin the turbine. Two least efficient thrust zones, near thetop and bottom walls, and a most efficient thrust zone, near the center,are depicted in FIG. 8 merely for illustrative purposes. It will beappreciated that in actuality the efficiency of the thrust variescontinuously from a minimum at the top to a maximum at the midpoint to aminimum at the bottom, with no abrupt break therebetween. In thismanner, the blades rotate continuously at a constant speed, without theaccelerations and decelerations which accompany turbines in which theblades pass discontinuously through the most efficient and leastefficient thrust zones.

A resolution of the thrust force exerted on each blade is illustrated inFIG. 9. The thrust A exerted on each blade 12 is perpendicular to theleading edge 36 of the blade. The component B, perpendicular to therotatable shaft 14, is the working component of the thrust A, thecomponent which pushes the blade with respect to the shaft. Thecomponent C, parallel to the rotatable shaft 14, exerts a force parallelto the shaft on the shaft bearings. By providing two halves withoppositely directed helixes, as shown in FIG. 5, these components canceleach other out, thereby minimizing wear on the shaft bearings. The angleγ, the angle made by the leading edge of the blade with respect to theshaft depends on the particular application.

The helical turbine is particularly suitable for hydro applicationswhere strong water currents develop, and may be installed on a vessel,as discussed further below, or in the body of any low-head dam in ariver. The helical turbine is also suitable for harnessing wind and waveenergy, as discussed below.

In a further embodiment of the present invention shown in FIGS. 17 and18, a distributor 206 comprising a generally cylindrical tubular memberis provided in the turbine between the helical blades 202 and the shaft214 to extend the length of the turbine between the turbine supports208. The distributor 206 is disposed circumferentially about the shaft214 and concentric with the helical blades 202. The distributor 206redirects the fluid streams inside the turbine toward the outsiderotating blades as indicated by arrows 210, thereby increasing the fluidflow near the blades and improving helical turbine efficiency and poweroutput. The distributor can be fixed to the shaft to rotate with theblades (discussed further below) or it can remain motionless withrespect to the blades, for example by providing suitable bearingsbetween the distributor and support discs. If mounted for rotation, thecylindrical distributor can be mounted to rotate with the same angularvelocity of the blades or a different angular velocity, as would beknown by those skilled in the art.

A small scale helical turbine was tested with and without a distributorboth in water and wind tunnels. The turbine was made from an epoxy-typeresin. The test results indicate that turbine velocities and poweroutput are substantially improved with inclusion of the fluiddistributor. A more than double increase in efficiency can be achievedin some applications compared with a turbine without a distributor.Although shown in FIG. 17 with the helical turbine of the presentinvention, the cylindrical distributor can also be used with theDarrieus turbine.

As shown in FIGS. 22 and 23, the helical turbine may also be providedwith multiple layers or rings 220, 222 of concentrically arrangedhelical blades. FIG. 22 illustrates two rings, each having three helicalblades. FIG. 23 schematically illustrates two rings each having twohelical blades. Although two rings are shown, any suitable number ofrings may be provided. Similarly, any suitable number of blades per ringmay be provided. The spirals of blades of adjacent rings may be, but arenot necessarily shifted with respect to each other to avoid shieldingthe inner blades by the outer blades. The multilayer arrangementprovides greater torque and higher power. The multilayer helical turbineis operable under the high water heads found in conventional powerplants, since the multiple rings increase resistance to the water flowmaintaining high water pressure.

The helical turbine of the present invention is shown in FIG. 10 inoperation in association with a hydro-pneumatic power generation system,such as that disclosed in U.S. Pat. Nos. 5,074,710 or 5,222,833. Asgenerally described above, the system comprises two water chambers 71,72 interconnected by ingress and egress ports 73, 74, 75, 76 on commonshafts. As the water level 77, 78 in the two chambers alternately risesand falls, air in the space above the water level is alternatelycompressed and expanded. The air flows through the channel 20interconnecting the two chambers, alternating directions in synchronismwith the rising and falling water levels.

The turbine 10 of the present invention is mounted within the channel.The flowing air causes the turbine to rotate as described above. Whenthe flow of water through the chambers reverses, the flow of air throughthe channel also reverses. However, the turbine continues to rotate inthe same direction. During the air flow cycle, the air flows in a firstdirection and the speed of the air increases to a maximum.

The turbine is connected in any suitable manner to an electric generator79 for generating electricity. The turbine can reach speeds of 1800 or3600 rpm with water heads of as low as one or two feet. Thus, the systemis suitable for generating power on rivers of small grades where highdams are not applicable.

The helical turbine of the present invention may be installed on avessel 120, as shown in FIGS. 11 through 13. The vessel 120 rises andfalls with the fluctuating water level 122, ensuring that the turbineremains always at the area of greatest velocity. A catamaraninstallation is shown in FIGS. 11 through 13, although any type ofvessel or raft may be used. A helical turbine 124 according to thepresent invention, such as described in reference to any of theembodiments described herein, is mounted to extend between two pontoonsor hulls 126, 128 of the catamaran and oriented perpendicularly to thecurrent flow, illustrated by arrows 130. The turbine 124 is mountedbelow the water's surface 122, so that all of the turbine is submerged.Water flowing past the turbine blades 132 causes the blades 132 andshaft 134 to rotate, as discussed above.

Generally, the turbine is mounted either in a housing 136 having aturbine chamber such as described above or without a housing. Thehousing, if employed, may have front and back openings 138 therein toallow the current flow 130 to pass through the housing 136 and past theturbine blades 132. The housing may be mounted to the pontoons 126, 128in any suitable manner. However, in some applications, such as if thecurrent velocity is sufficiently great, the housing may not need to beprovided. The shaft 134 may be connected to an electric generator 140 inany suitable manner, such as by a belted transmission 142. As shown, theelectric generator may be housed in a suitable water tight chamber 144on the vessel if desired.

In a further embodiment, the helical turbine can be efficientlyconfigured as an optimal unit or module and combined in a modular arrayto harness water or wind power. The power available from a prior artpropeller turbine is proportional to the circumferential velocity of theblades, which increases with distance from the turbine shaft. Thus,prior art turbines are traditionally designed with a maximum diameter.However, the size of such prior art turbines is limited by theirstrength and possibility of structural failures caused by centrifugalforces and vibrations when the diameter becomes too large. The helicalturbine is advantageous in this regard, since its available power isproportional to a frontal rectangular area equal to the product of itsdiameter and its length, and the length is not related to angularvelocity or centrifugal forces. A relatively small helical turbinemodule can be optimized for airfoil profile, angular velocity, diameter,and length, and an entire power system can be assembled from suchmodules. Such a power system can exploit a common shaft and generatorfor a number of modules and is simple to build and maintain.

A suitable helical turbine module 304 is shown in FIG. 14. The modulecomprises one or more helical blades 302 arranged in a spiral about acentral shaft 314. Generally, at least two helical blades are used. Theblades are attached to a turbine support, such as one or more discs 308or radial spokes, which is connected to the central shaft 314, asdiscussed above. Preferably, the blades are made from a material whichis strong and lightweight, such as aluminum or fiberglass, and may behollow if desired.

FIG. 15 illustrates a turbine module 304 such as in FIG. 14 combined inan array for harnessing wind power, in which the fluid flow can bemultidirectional. The modules are stacked vertically end to end.Preferably, the modules are arranged with the direction of the spiralsalternating, such that one module is left handed and an adjacent moduleis right handed. A plurality of vertically stacked modules are arrayedadjacent to each other to provide a wall 312 of turbine modules. Eachvertical stack may be supported in any suitable manner. For example,structural members may be arranged to form a lightweight rectangularframe or truss 216, such as an antenna-type structure, around thevertical stack and anchored to the ground by guy wires 318. Any desirednumber of modules may be provided in any desired number of verticalstacks. One or more electrical generators 320 are provided incommunication with the vertical shafts. A generator may be individuallyassociated with each shaft, or plural shafts may be connected via asuitable transmission to a single generator, as shown in FIG. 21. Thearray of modular turbines may be located in any suitable windy location,as is known in the art, for example for locating traditionalwindmill-type wind farms.

A further modular embodiment is shown in FIG. 16, in which turbinemodules 304 such as in FIG. 14 are arranged in a horizontalconfiguration. A plurality of horizontally disposed shafts 322 arearrayed vertically in a plane and supported at their ends by suitabletruss members arranged to form a lightweight frame 324. The frames areanchored to the ground with guy wires 326. A plurality of generators aresupported by the frames in communication with the shafts. Any desirednumber of modules may be provided in any desired number of rows. Therows may be of any desired length, and any suitable number of frames maybe provided to support the desired length.

The array of modular helical turbines is advantageous since it exploits100% of the rectangular swept cross-sectional area of the blowing windas well as being self-starting. Traditional propeller-type wind turbinesin contrast, must be rotated to face the wind direction and sweep acircular cross-sectional area. The helical turbines provide a uniformnon-oscillating rotation, as compared to the prior art Darrieusturbines. The turbines provide unidirectional rotation for any winddirection except parallel or nearly parallel to the shaft, for whichcase no or very little power can be developed. Also, birds are likely toperceive the array of rotating helical turbines as a solid wall,minimizing the danger of collisions, or the turbine modules can bescreened to prevent collisions with birds. The modular system andlightweight frames provide for structural strength and simplicity inassembly and maintenance.

The modular helical turbines are useful in other applications, such asin tidal straight or reversible water currents with no dam construction,or in ultra low-head (less then ten feet) hydropower plants, in, forexample, rivers, canals, or tidal estuaries. The modules can be used forsmall power sources in ocean currents to supply lights or other oceanelectrical apparatus. In conventional power plants, the modular helicalturbine can be combined in long chains or arrays, which is not possiblewith conventional propeller type turbines.

The helical turbine of the present invention is also useful to providepropulsion or supplement engine-driven propulsion of a marine vesselutilizing the power of ocean waves. The helical turbine is operableunder the multidirectional oscillations of ocean waves. Thus, thehelical turbine can develop an axial torque useful in the propulsion ofmarine vessels.

As shown in FIGS. 19 and 20, a helical turbine 400 as described above ismounted along each side 402, 404 of a ship 406 below the water line 408.A propeller 410 is mounted in any suitable manner to the end of eachturbine's shaft. Although two turbines are shown, any number, includingone, could be used. The turbines provide unidirectional rotationindependent of the directions of the waves' oscillations. The turbinesare aligned along the ship 406 to provide a forward direction of motion.The longer the turbine's length, the greater the amount of wave powerthat can be harnessed. The length of the turbines are limited only bythe length of the ship.

The helical turbines 400 are beneficial as a propulsion source orsupplement, since they are not polluting, are quiet, and conserve fuelrequired by the ship's engines. Also, the turbines stabilize the ship'srocking by utilizing the wave energy.

The helical turbine in a vertical orientation may also be used as a windsail for a ship. As shown in FIG. 26, a suitable number of helicalturbine modules 601 are attached to the deck of a vessel 602 by alightweight frame 603 anchored by guy wires 604. In this case, asuitable transmission 605 for interconnection to a horizontal shaft andpropeller 606 are provided.

Lifting or lowering of an object in water can also be accomplished withthe helical turbine in combination with the cylindrical distributormounted for rotation with the turbine shaft. The rotating cylinderdevelops a lifting or lowering force depending on the direction ofrotation. For example, if the cylinder is rotating such that its uppersurface is moving in the direction of the current flow, the relativevelocity of the upper surface with respect to the current flow increasesand the pressure thereon decreases, while the relative velocity of thelower surface decreases and the pressure thereon increases. Thus, a liftforce is developed on the cylinder. Similarly, if the cylinder rotatesin the opposite direction, a lowering force is developed on thecylinder.

Accordingly, relative to a flowing current of water, the rotatingcylinder, driven by the helical turbine, can be used to raise or loweran object in water. No additional motor is needed to rotate thecylinder. For example, as shown in FIGS. 24 and 25, a tug boat 501dragging a plurality of helical turbines 502 and cylinders 503 attachedto the sides of a submerged object such as a cargo barge 504 can be usedto maintain floatation of or tow the submersible barge without an engineto drive the turbines. The barges can be relatively long and large tohold large amounts of cargo and can be larger than the tug boat.

The invention is not to be limited by what has been particularly shownand described, except as indicated by the appended claims.

What is claimed is:
 1. A system for harnessing the energy of amultidirectional fluid flow comprising:a rotatable shaft; a generator incommunication with said rotatable shaft; and a plurality of cylindricalhelical turbine modules supported on said rotatable shaft, each turbinemodule comprising a turbine capable of unidirectional rotation undermultidirectional fluid flow, said turbine further comprising:at leastone turbine blade support member fixedly mounted to said rotatable shaftfor rotation therewith in a plane perpendicular to said shaft; and aplurality of turbine blades having a fixed cylindrical helicalconfiguration and mounted to said turbine blade support member forrotation about an axis of said rotatable shaft, each blade having anairfoil shape having a leading edge and a trailing edge and an airfoilprofile lying in a plane parallel to a component of the fluid flow, eachof said blades fixedly mounted to said blade support member to beradially spaced from said rotatable shaft for rotation in the planeperpendicular to said shaft in a direction of said leading edge.
 2. Thesystem of claim 1, wherein said plurality of modules are arrangedvertically.
 3. The system of claim 2, wherein said plurality of modulesare supported by a structure anchored to the ground by guy wires.
 4. Thesystem of claim 1, wherein said plurality of modules are arrangedhorizontally.
 5. The system of claim 4, wherein said plurality ofmodules are supported at ends thereof by a lightweight structureanchored to the ground by guy wires.
 6. The system of claim 1, whereinsaid plurality of blades comprises two helical blades.
 7. The system ofclaim 1, wherein said plurality of helical turbine modules is arrangedto harness wind flow.
 8. The system of claim 1, wherein said pluralityof helical turbine modules is arranged to harness water flow.
 9. Asystem for harnessing the energy of a multidirectional fluid flowcomprising:an array of cylindrical helical turbine modules comprising:aplurality of rotatable shafts, each of said rotatable shafts supportedby a structure anchored to the ground by guy wires; at least onegenerator in communication with said plurality of rotatable shafts; andwherein each turbine module is supported on one of said plurality ofrotatable shafts, each turbine module comprising a turbine capable ofunidirectional rotation under multidirectional fluid flow, said turbinefurther comprising:at least one turbine blade support member fixedlymounted to said one of said plurality of rotatable shafts for rotationtherewith in a plane perpendicular to said shaft; and a plurality ofturbine blades having a fixed cylindrical helical configuration andmounted to said turbine blade support member for rotation about an axisof said one of said plurality of rotatable shafts, each blade having anairfoil shape having a leading edge and a trailing edge and an airfoilprofile lying in a plane parallel to a component of the fluid flow, eachof said blades fixedly mounted to said blade support member to beradially spaced from said rotatable shaft for rotation in the planeperpendicular to said shaft in a direction of said leading edge.
 10. Thesystem of claim 9, wherein said plurality of shafts are arrangedvertically.
 11. The system of claim 9, wherein said structure comprisesa frame or a truss.
 12. The system of claim 9, wherein said plurality ofshafts are arranged horizontally.
 13. The system of claim 12, whereinsaid plurality of shafts are supported at ends thereof by saidstructure.
 14. The system of claim 9, wherein said array of turbinemodules is arranged to harness wind flow.
 15. The system of claim 1,wherein the plurality of helical blades comprise two blades withoppositely directed helixes arranged to overlap a cross-sectionalcircumference of said turbine.
 16. A system for harnessing the energy ofa multidirectional fluid flow, comprising:a turbine support disposed ina flow path of the fluid flow; and a turbine capable of unidirectionalrotation under multidirectional fluid flow and mounted to said turbinesupport, said turbine comprising:a rotatable shaft mounted to saidturbine support to extend perpendicularly to a direction of fluid flow;at least one turbine blade support member fixedly mounted to saidrotatable shaft for rotation therewith in a plane perpendicular to saidshaft; and a plurality of turbine blades having a fixed cylindricalhelical configuration mounted to said turbine blade support member forrotation about an axis of said rotatable shaft, each blade having anairfoil shape having a leading edge and a trailing edge and an airfoilprofile lying in a plane parallel to the direction of fluid flow, eachof said blades fixedly mounted to said blade support member to beradially spaced from said rotatable shaft for rotation in the planeperpendicular to said shaft in the direction of said leading edge. 17.The system of claim 16, further comprising a generator mounted to saidturbine support in communication with said turbine.